playcanvas
Version:
PlayCanvas WebGL game engine
127 lines (125 loc) • 3.19 kB
JavaScript
var gsplatCommonVS = `
struct SplatSource {
order: u32,
id: u32,
uv: vec2<i32>,
cornerUV: vec2f,
}
struct SplatCenter {
view: vec3f,
proj: vec4f,
modelView: mat4x4f,
projMat00: f32,
}
struct SplatCorner {
offset: vec2f,
uv: vec2f,
aaFactor: f32,
}
fn quatToMat3(R: vec4<f32>) -> mat3x3<f32> {
let R2: vec4<f32> = R + R;
let X: f32 = R2.x * R.w;
let Y: vec4<f32> = R2.y * R;
let Z: vec4<f32> = R2.z * R;
let W: f32 = R2.w * R.w;
return mat3x3<f32>(
1.0 - Z.z - W, Y.z + X, Y.w - Z.x,
Y.z - X, 1.0 - Y.y - W, Z.w + Y.x,
Y.w + Z.x, Z.w - Y.x, 1.0 - Y.y - Z.z
);
}
const SH_COEFFS: i32 = 3;
const SH_COEFFS: i32 = 8;
const SH_COEFFS: i32 = 15;
const SH_COEFFS: i32 = 0;
fn clipCorner(corner: ptr<function, SplatCorner>, alpha: f32) {
let clip: f32 = min(1.0, sqrt(-log(1.0 / (255.0 * alpha))) / 2.0);
corner.offset = corner.offset * clip;
corner.uv = corner.uv * clip;
}
const SH_C1: f32 = 0.4886025119029199;
const SH_C2_0: f32 = 1.0925484305920792;
const SH_C2_1: f32 = -1.0925484305920792;
const SH_C2_2: f32 = 0.31539156525252005;
const SH_C2_3: f32 = -1.0925484305920792;
const SH_C2_4: f32 = 0.5462742152960396;
const SH_C3_0: f32 = -0.5900435899266435;
const SH_C3_1: f32 = 2.890611442640554;
const SH_C3_2: f32 = -0.4570457994644658;
const SH_C3_3: f32 = 0.3731763325901154;
const SH_C3_4: f32 = -0.4570457994644658;
const SH_C3_5: f32 = 1.445305721320277;
const SH_C3_6: f32 = -0.5900435899266435;
fn evalSH(source: ptr<function, SplatSource>, dir: vec3f) -> vec3f {
var sh: array<vec3f, SH_COEFFS>;
var scale: f32;
readSHData(source, &sh, &scale);
let x = dir.x;
let y = dir.y;
let z = dir.z;
var result = SH_C1 * (-sh[0] * y + sh[1] * z - sh[2] * x);
let xx = x * x;
let yy = y * y;
let zz = z * z;
let xy = x * y;
let yz = y * z;
let xz = x * z;
result = result + (
sh[3] * (SH_C2_0 * xy) +
sh[4] * (SH_C2_1 * yz) +
sh[5] * (SH_C2_2 * (2.0 * zz - xx - yy)) +
sh[6] * (SH_C2_3 * xz) +
sh[7] * (SH_C2_4 * (xx - yy))
);
result = result + (
sh[8] * (SH_C3_0 * y * (3.0 * xx - yy)) +
sh[9] * (SH_C3_1 * xy * z) +
sh[10] * (SH_C3_2 * y * (4.0 * zz - xx - yy)) +
sh[11] * (SH_C3_3 * z * (2.0 * zz - 3.0 * xx - 3.0 * yy)) +
sh[12] * (SH_C3_4 * x * (4.0 * zz - xx - yy)) +
sh[13] * (SH_C3_5 * z * (xx - yy)) +
sh[14] * (SH_C3_6 * x * (xx - 3.0 * yy))
);
return result * scale;
}
`;
export { gsplatCommonVS as default };